Method of constructing one-piece pire-brick arch



W..A. L. SCHAEFER.

METHOD OF CONSTRUCTING ONE-PIECE FIRE BRICK ARCH.

APPLICATION FILED APR-9, 1919,

1,341,077. atented May 25, 1920.

Jmerzzcrfl W QL Jcfzaefer UNITED STATESIPATENT OFFICE.

WILLIAM A. I:- SCHAEFER, OF CHICAGO, ILLINOIS, ASSIGNOR TO JOINTLESS FIRE BRICK COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

mambo or CONSTBUCTING ONE-PIECE FIRE-BRICK ARCH.

Specification of Letters Patent.

Patented May 25, 1920.

Application filed "April 9, 1919. Serial No. 288,742.

To all whom it may concern Be it known that I, WILLIAM A. L. SCIIA'EIER, a citizen "of the United States, residin at Chicago, in the county of Cook and tate of Illinois, have invented acertain new and useful Improvement in Methods of Constructing One-Piece Fire-Brick Arches, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawin s, forming a part of this specification.

li Iy invention relates to one-piecc fire brick arch and method of constructing same.

Heretofore, in the art one of the most serious difiicultiesencountered in the setting of various boilers has been that of constructing the various arches thereof. This is particularly the case in connection with tubular boilers, the rear or back combustion cham' ber arches of which have been extremely difficult to construct of ordinary fire brick. Arches of this general descrlption have heretofore in the art been constructed of a plurality of fire bricks of various shapes and sizes laid up with a fire clay mortar. I have observed that in addition to the porosity of such brick and the expense involved in frequent cutting thereof, that the numerous joints have been unable to withstand the destructive forces to which they are subjected, allowing an inflow of excessair to the combustion chamber.

In addition to the necessity of being absolutely gas tight, allowance must be made in such an arch for expansion and contraction of the boiler.

It is an aim of the present invention to in crease boiler efficiency and fuel economy by providing for the easy and economical installation of an airtight, refractory, onepie'ce arch, preferably of the plastic fire brick material disclosed in my co-pending application, Serial Number 288,745, filed April 9, 1919; although it is to be understood that any material of similar characteristics may be used instead. The material disclosed in the above application is particularly valuable because of its ability to withstand extremely high temperatures, its refract'ory qualities, its freedom from deformation and shrinkage, either permanent or due to temperature changes, its adaptability to be readily molded or shaped to structures of various shapes and sizes, and above all,

it will not leak air or gas, and it will not crack or spall.

It is a further aim of the present invention to provide a refractory one-piece fire brick arch, which, in addition to being absolutely gas and air tight, will allow for expansion and contraction of the boiler.

Frequent renewals of the various arches in boiler settings has heretofore been necessary, due to the cracking or breaking ofi' of the corners of the various brick. The present invention provides for the installation of a smooth, continuous fire brick arch,

wherein such corners or edges are elimi nated.

A still further aim oi. the present invention is the provision otan improved form or false work construction for centering and supporting the plastic arch, which false work construction will in no event burn out until the plastic arch has been baked into a one-piece jointless arch, capable of standing up without support.

In order that those skilled in the art may be fully acquainted with the nature and scope of the present invention, I shall describe a specific embodiment of the invention. in connection with. the accompanying drawing, which illustrates in perspective with portions broken away the method of constructing an arch in accordance with the teachings of the present invention.

Referring to the drawing, it will be seen that a one-piece, fire-brick arch 1 has been installed over the combustion chamber 2 to the rear of the tubular boiler 3. This arch, while capable of standing up alone after the plastic fire brick material has been converted into fire-brick by heat, must be supported while in its plastic condition.

The metallic plate or sheet at ior bracing or supporting the one-piece arch 1 while in the plastic condition is first shaped to the particular arched form desired for the bottom of the arch. One end of this plate then secured or anchored in the common brick rear wall 5 of the boiler setting, as shown at 6. The arched plate or sheet is supported-in this particular instance-id tel-mediate its length and at its opposite end adjacent the head of the boiler 33 by means of a pair of bars or pipes 7, which bars or pipes 7 extend transversely through the combustion chamber 2 adj acent the up per edge thereof, and are secured in the opposite common brick side walls respectively of the boiler setting.

A suitable packing 8-such as, for example, rope asbestos-is installed adjacent the head of the boiler 3 to insure the arch from being cracked or otherwise damaged by expansion and contraction of the boiler. The plastic fire brick material is then installed upon the arched plate 4c in chunks, each chunk being thoroughly pounded and worked to insure proper union with the previously installed portions of the arch. The plastic arch is built up to the form or con tour of the arch desired, being built upto the asbestos packing 8 as shown.

The common brick side and rear walls of the boiler setting are preferably provided with a one-piece, fire-brick lining 9, formed of the same material and continuous with the arch 3, the corners of which lining are rounded into the one-piece arch, making a straight, jointless one-piece setting for the boiler 3. In the installation of the onepiece lining 9, I have found it to be advisable to bond the plastic walls into the common brick walls of the setting by removing the headers from the common brick walls and pounding the plastic material thoroughly into the spaces provided thereby. It is further advisable to brush the common brick walls thoroughly with a suitable binder before the installation of the plastic firebrick material.

Upon completion of the plastic fire brick arch 1 and the plastic lining formed continuous therewith, the arch is dried out by means of a slow wood or banked coal fire, the arched supporting plate 4 and the bars or pipes 7 being thoroughly heated thereby, but not sufficiently to burn the same out, after the moisture has been thoroughly removed, the heat is gradually increased to bake the plastic material into a solid, onepiece, jointless arch. The high temperatures eventually attained in the combustion chamber 2 will burn out the arched plate or sheet 4, and the bars or rods 7 supporting the same, but not until the plastic arch has been baked into a solid, one-piece, refractory arch, capable of standing up without support.

The secure anchoring of the arched plate orsheet 4c and the plastic fire brick arch l in the adjacent common brick walls of the boiler setting, together with the allowance made for expansion and contraction of the boiler, are highly important aspects of the present invention.

VVhil'e I have described the present invention with reference to the details of a particular embodiment, it is to be understood that this embodiment is merely illustrative, and it will at once be apparent to those skilled in the art, that the invention may appear in other forms, and he used for other purposes, without departing from the spirit and scope of my invention.

I claim:

1. The method of constructing a one-piece fire-brick arch consists in arranging a bar or pipe through the boiler setting, anchoring the opposite ends of said bar or pipe in the walls of said boiler setting, then anchoring one end of a metallic sheet or plate in one of the walls of the boiler setting, supporting the opposite end of said sheet or plate upon said bar or pipe and then in stalling a mass of plastic fire-brick material upon said metallic sheet in the form of the desired arch.

2. The method of constructing a one-piece fire brick arch, which consists in arranging a bar or pipe through the boiler setting, anchoring the opposite ends of said bar or pipe in the walls of said boiler setting, then anchoring one end of a metallic sheet or plate in one of the walls of the boiler setting, supporting the opposite end of said sheet or plate upon said bar or pipe, then installing a mass of plastic fire-brick material upon said metallic sheet in the form of the desired arch, then heating the false work structure and the arch formed to convert the plastic material into fire-brick and thereafter burning out said bar or pipe and said metallic plate.

3. The method of constructing a one-piece fire-brick arch, which consists in anchoring a false work structure in the walls of the boiler setting, supporting a metallic sheet or plate thereupon, then installing a mass of plastic fire-brick material upon said metallic sheet or plate in the form of the desired arch, then heating the false work structure and the arch formed to convert the plastic material into fire-brick and thereafter burning out the false work structure.

4. The method of constructing a one-piece fire-brick arch, which consists in anchoring a false work structure in the walls of the boiler setting, arranging a metallic sheet or plate upon said anchored false work structure, anchoring said metallic sheet or plate in one of the walls of the boiler setting and then installing a mass of plastic fire'brick material upon said metallic sheet or plate in the form of the desired arch.

5. The method of constructing a oncpiecc fire-brick arch which consists in anchoring a metallic sheet or plate in the wall of the boiler setting, fixedly against removal therefrom, then installing a mass of plastic firebrick material upon said metallic sheet or plate in the form of the desired arch and thereafter burning out said metallic sheet or plate.

6. The method of constructing a one-piece fire-brick arch which consists in anchoring a metallic sheet or plate in the wall of the boiler setting and then installing a mass of plastic fire-brick material upon said metallic sheet or plate in the form of the desired arch.

7. The method of constructing a one-piece fire-brick arch which consists in building false work structure of metal bars or pipes supporting a metallic sheet or plate, then installing a mass of plastic fire-brick material upon said metallic plate in the form of the desired arch, then heating the false work structure and the arch formed to convert the plastic material into fire-brick and thereafter burning out the false work structure.

8. The method of constructing a one-piece firebrick arch which consists in arranging a bar or pipe through the boiler setting, an-

choring the opposite ends of said bar or pipe in the walls of said boiler setting, then anchoring one end of a metallic sheet or plate in one of the walls of the boiler setting, sup porting the opposite end of said sheet upon said bar or pipe, then installing a suitable packing adjacent the boiler to allow for expansion and contraction thereof and then installing a mass of plastic fire-brick ma terial upon said metallic sheet or plate up to said packing in the form of the desired arch.

In witness whereof I hereunto subscribe my name, this 2% day of March, 1919.

WILLIAM A. L. SCHAEFER. 

